WildFly HornetQ-Based Messaging Subsystem Concepts

External

• Messaging chapter in "EAP 6.4 Administration and Configuration Guide" https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/html/Administration_and_Configuration_Guide/chap-Messaging.html

Internal

• WildFly Messaging Subsystem

Persistence

HornetQ does not support database-based persistence. For reasons that went into this decision see https://developer.jboss.org/thread/153581. More details in "Messaging persistence in EAP 6.x" https://access.redhat.com/solutions/226743.

Journal

When a node is started for the first time it persists a unique identifier into its journal directory. This ID is needed for proper formation of clusters.

Clustering

Migrating From https://home.feodorov.com:9443/wiki/Wiki.jsp?page=HornetQClusteringConcepts

• Administation and Configuration Manual - HornetQ Clustering https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/html/Administration_and_Configuration_Guide/sect-HornetQ_Clustering.html

Clustering in this context means establishing a mesh of HornetQ brokers. The main purpose of creating a cluster is to spread message processing load across more than one node. Each active node in the cluster acts as an independent HornetQ server and manages its own connections and messages.

Connections between nodes are explicitly declared in configuration. Messages are passed between nodes over core bridges. Core bridges consume messages from a source queue and forward them to a target queue deployed on a HornetQ node which may or may not be in the same cluster. When a node forms a cluster connection with another node, it automatically creates a core bridge internally. For more details on how to configure a WildFly HornetQ-based messaging cluster see:

WildFly HornetQ-Based Messaging Subsystem - Clustering with TCP

High Availability

• EAP 6.4 Administration and Configuration Guide - HornetQ High Availability https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.3/html/Administration_and_Configuration_Guide/sect-High_Availability.html

WildFly Clustering and HornetQ High Availability

HornetQ High Availability is configured independently of WildFly Clustering, so a configuration in which WildFly nodes are running in a non-clustered configuration but the embedded HornetQ instances are configured for High Availability is entirely possible.